Krishnan rxns and Other Notes

Question 1

Answer 1

Dehydration: The electrons on the OH takes the proton from the acid and makes a water group on the ring. The water molecule acts a s leaving group which makes a carbocation. Then the base (in this situation, water) abstracts the proton on the carbocation and the electrons from the H bond on the ring goes to the adjacent carbon on the ring.

Question 2

Answer 2

Question 3

Answer 3

Question 4

Answer 4

Dehydrohalogenation: The bromine acts as a leaving group and the first reagent disassociates to create a positive molecule (K+, or Na+) and a negatively charged molecule (O^-CH2CH3). (O^-CH2CH3 abstracts the hydrogen on the adjacent carbon and the e- that was once had by the proton creates a double bond on the most substituted carbon.

SN1 which means its a stepwise reaction where the bromide leaves first (creating stable carbocations) and the bond from the hydrogen goes to the adjacent carbon. Same applies to secondary halides

Question 5

What are the preferred conditions for a primary halide? What kind of reaction is it? Explain

Answer 5

It is a SN2 reaction where the steps are concerted. In this situation the negatively charged base (dissociated Potassium Tertbutoxide) abstracts the proton and the bond from the hydrogen goes to the adjacent carbon

Question 6

Answer 6

Question 7

Answer 7

Question 8

Answer 8

removes double bond and places hydrogens on each side of the eliminated pi bond

Question 9

Answer 9

Pi bond attracts proton, getting rid of the double bond and the most substituted carbon becomes a carbocation for the negatively charged halogen to take its place.

Question 10

Answer 10

Negatively charged pi bond abstracts a proton form the acid, leaving a carbocation and an H bond where the pi bond used to be.

Negatively charged lone pairs on the water molecule attaches to the carbocation

Another water molecule abstracts a hydrogen from the water group on the structure leading the bond from the hydrogen to attack the positively charged oxygen in the structure making the OH group neutral

Question 11

Answer 11

Question 12

Answer 12

Question 13

Answer 13

Question 14

Answer 14

Question 15

Answer 15

makes pi bonds in the presence of halides

Question 16

Answer 16

Question 17

Answer 17

removes just 1 pi bond

Question 18

Answer 18

enol to ketone

Question 19

Answer 19

2 Bromines added to the end of the pi bonds for each pi bond

Question 20

Answer 20

Question 21

Answer 21

insert the “O” to the = bond and the -OH to the - bond

Question 22

How are free radicals formed?

Answer 22

Question 23

Answer 23

Remember that a secondary radical is more stable than primary ones so the secondary radical will be used to proceed with the reaction

Question 24

Answer 24

Question 25

Answer 25

Question 26

Answer 26

Question 27

Answer 27

HCl will dissociate into H+ and Cl-. The negatively charged lone pairs on the OH on the benzylic carbon will snatch a proton and make OH into a water molecule. The water molecule will leave creating a secondary carbocation. The Carbocation will then attract the negatively charged Cl- and create the product you see here.

Question 28

What is the reference compound used in HNMR spectroscopy?

Answer 28

TMS

Question 29

What are heterocyclic compounds?

Answer 29

Compounds that contain at least one atom other than carbon within their ring

Question 30

What are examples of heterocyclic compounds (4)? Name and draw them

Answer 30

Question 31

How do you find out if something is aromatic?

Answer 31

4n+2 = #πe- where n has to be an integer

Question 32

Is this aromatic? Show your work?

Question 33

Where are the different types bonding orbitals placed in the frost cycle?

Answer 33

Question 34

What does pyridine look like?

Answer 34

Question 35

What does pyrrole look like?

Answer 35

Question 36

What does furan look like?

Answer 36

Question 37

what does thiophene look like?

Answer 37

Question 38

Answer 38

Question 39

What do Electron Withdrawing Groups (EWGs) do? What are some examples of EWGs in order from stongest to weakest (5)? Are they ortho, meta, or para directing?

Answer 39

They pull electrons away from the molecule’s core. Ex) Nitro Groups, CF3, C≡N, C=O, Halogens (Ortho Para Directing)

Question 40

what are methoxy groups?

Answer 40

Question 41

What is a alkyl group?

Answer 41

Carbon-hydrogen bonds

Question 42

what is an amine?

Answer 42

NH2

Question 43

What do Electron Donating Groups (EDGs) do? What are some examples of EDGs in order from stongest to weakest (5)? Are they ortho, meta, or para directing?

Answer 43

They donate electrons to a molecule. Ex) N:, O:, alkyl groups, Ar, and C=C. Ortho Para Directing

Question 44

Answer 44

You will add SO3H to the benzene ring. You add it to the meta position in relation to the nitro group because its a very strong EWG (which are meta-directing).

Question 45

What is the order of EDG/EWG stuff. pt1.

Answer 45

These are EDGs

Question 46

What is the order of EDG/EWG stuff. pt2.

Answer 46

Question 47

Answer 47

Question 48

Answer 48

Question 49

Answer 49

Question 50

Answer 50

Question 51

Answer 51

Question 52

Answer 52

When activating effects are similar, substitution ortho to the smaller group is favored.

Question 53

Answer 53

naphthalene

Question 54

Answer 54

anthracene

Question 55

Answer 55

phenantherene

Question 56

Answer 56

Makes benzoic acid on the benzylic carbon. Same can be said for ethyl, propyl, buta, etc. No reaction on tertbutyle alkyls.

Question 57

Answer 57

Cuts the pi bond and makes OHs on each side of the pi bond

Question 58

Answer 58

Question 59

Answer 59

converts aldehydes and ketones into alkanes

Question 60

Answer 60

Question 61

Answer 61

makes carboxylic acids on benzylic positions